This "castle" is actually a limestone and quartz formation hidden along a trail.

A natural spring situated on the grounds of the Hawthorne estate.

The last of nine massive kilns that produced many of the red bricks for buildings in Washington, D.C. and northern Virginia in the early 20th century.

Memorial stone for GWAR vocalist, depicted in his iconic costume.

A 14-foot monument marks the resting place of two of the town's earliest residents—and one unknown soldier.

This sprawling farm was once a Cold War-era hideaway for the nation's top diplomats.

Though it was originally dedicated to the Hindu god Shiva, Baphuon was converted to a Buddhist temple in the 15th century, complete with a massive hidden statue.

The capital of Cambodia is named after the hill on which this ancient temple complex stands.

A small 12th-century temple surrounded by waters believed to have curative properties.

This Cambodian riverbed is covered in ancient Hindu carvings both above and below the waters.

A line of disused military bunkers built to defend against Nazi invasion lies hidden on the outskirts of the city.

Collection dedicated to funeral rites, equipment, and mourning rituals of the Viennese.

The haunting cadaver tomb of a famous French poet, playwright, and filmmaker.

This fascinating abbey is considered the oldest monastery in the region.

The first national memorial to honor all women suffragists stands on land where suffragists were once imprisoned.

The all-but-forgotten cemetery is Eastern Loudon County's largest African-American burial ground.

Once known as the Illinois Asylum for the Incurable Insane.

This bar is filled with Star Wars merchandise from around the world, all of it unlicensed knockoffs.

This homestead was occupied by Union soldiers, who believed the owners were signaling Confederate forces.

This defunct, fortress-like prison has been the setting for several movies.

Dinosaurs invade a suburban Nashville neighborhood.

The ruin of a Japanese love hotel almost completely overgrown with brambles.

A line of abandoned, alien-like fortresses dot the mountains of North Italy.

This entire town moved to a safe location after it was devastated by an earthquake, but the remains of the original town are still around.